JPH0143840Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field] The present invention relates to a load output adjustment device for lighting a lighting load by stepwise dimming.

[Background technology]

Although various types of dimming control methods have been provided in the past, a dimming control method using phase control is generally adopted in cases where a large number of lighting loads are to be dimmed all at once. However, in the case of a dimming device using such a phase control method, distortion as shown in Fig. 1 occurs in the input power supply voltage waveform, and the input current waveform contains many harmonic components, so the power supply feedback is There is a problem in that noise is generated and causes interference with other electronic precision equipment, resulting in negative effects.To prevent this, it is necessary to take measures to prevent power waveform distortion, such as adopting a noise prevention circuit, which requires expensive A serious problem arose.

[Purpose of invention]

The purpose of the present invention is to provide a load output adjustment device that can easily adjust the load output without causing problems such as noise generation under conditions where commercial power supplies of different voltages are supplied in close proximity to each other. It is something to do.

[Disclosure of invention]

FIG. 2 shows a circuit diagram of an embodiment of the present invention. For example, in a late-night store (convenience store), there are many shoppers until around 1 a.m., then there are few customers until around 5 a.m., and then there are fewer customers until around 5 a.m. If there are a certain number of visitors from 5:00 to 9:00, the third
There arises a need to control the dimming of a lighting fixture to achieve the illumination state shown in the figure, and the circuit of the embodiment shown in FIG. 2 is provided in order to be able to adapt to such needs. However, in the embodiment circuit shown in FIG. 2, power supplies 1 and 2 of 200V and 230V are selected as power supplies of different voltages close to each other, and power is selectively supplied by a dimming control switch 3 which also serves as a power-on switch element. In addition to the lighting circuit of part A and the normal stage dimmable fluorescent lamp 4, the dimming contact 1 detects changes in the receiving voltage.
The lighting fixture B includes a dimming control circuit 6 that opens and closes a light control circuit 5. That is, in the lighting fixture B, a starter 7 is attached in parallel to the fluorescent lamp 4, and a chiyoke coil 8 as a ballast and a current limiting inductance 9 for dimming are installed in series with the fluorescent lamp 4.
By connecting these, a lighting circuit for normal stage dimming is constructed. The dimming control circuit 6 also includes a diode bridge 10 that rectifies the power input, a resistor 11 connected to the output of the diode bridge 10 and forming a series closed circuit, a relay 12, and an SSS (silicon symmetrical switch). It is composed of a voltage switch element 13 and a capacitor 14 connected between the output terminals of the diode bridge 10, and the power-on detection circuit section is composed of the diode bridge 10, the capacitor 14, and a resistor 11 serving as a discharge resistor. A control circuit is constructed of a relay 12 and a voltage switch element 13 which is a voltage responsive switch, and the contacts of the relay 12 are connected in parallel to the aforementioned current limiting inductance 9 as a dimming contact 15. FIG. 4 is an explanatory diagram of the operation of the embodiment circuit of FIG. 2, in which FIG. 4a shows the voltage supplied from the power supply section A, and FIG. 4b shows the illumination dimming state of the lighting fixture B, respectively.

Thus, in the embodiment circuit shown in FIG. 2, if the dimming control switch 3 is now connected to the low contact on the 200V power supply 1 side and the AC 200V power supply 1 is supplied to the lighting fixture B, then the dimming contact 15 is closed, the fluorescent lamp 4 is stably lit via the chiyoke coil 8, resulting in a 100% full lighting state. Here, the starter 7 operates to start the fluorescent lamp 4 and does not have any effect while the lamp is lit, but in some cases, it may flow a preheating current during dimming to maintain the dimmed lighting. In addition, the lamp may be operated to prevent a reduction in lamp life. Also, at this time, the dimming contact 15 is closed as described above, but this is because the voltage switch element 13 has set the breakover voltage V _BO in advance so that it turns off when the input voltage is 200V and turns on when the input voltage is 230V. Since this is selected, the relay 12 is not energized and the dimming contact 15 made up of the NC contact is maintained in the closed state. Next, at time t ₁ in FIG. 4, the dimming control switch 3 is switched from the 200V side B contact to the 230V side A contact, and when the AC 230V power supply 2 is connected to the lighting fixture B side, the diode bridge 10 Through this, the capacitor 14 is charged with a higher voltage than when the voltage is 200 VAC, so that the voltage switch element 13
exceeds the breakover voltage V _BO , voltage switch element 13 is turned on, relay 12 is energized, and its
The dimming contact 15 consisting of an NC contact is opened. For this reason, a current limiting inductance 9 is inserted into the circuit of the fluorescent lamp 4 to limit the lamp current. As a result, the brightness is adjusted to 65% according to the preset value of the current limiting inductance 9.
Next, at time _t2 , when the dimming control switch 3 is switched to the 200V side (low) contact again, the discharge time of the capacitor 14 is delayed by the resistor 11 and the DC resistance of the relay 12, and the holding current of the voltage switch element 13 is By ensuring this, the voltage switch element 13 will continue to be on. Therefore, from time t ₂ to time t ₃ , the lighting is dimmed at 200 VAC and the brightness is 50%. Next, at time t ₃ , operate the dimming control switch 3 again and switch from the 200V AC B contact side to the AC 230V I contact side, and the voltage switch element 1 will change as described above.
3 remains on and maintains the dimming state, eventually becoming about 15% brighter to compensate for the increase in input voltage.
The light is dimmed to about 65% brightness. Furthermore, when returning to the 100% lighting state, connect the dimming control switch 3 to the unconnected contact C, and connect the capacitor 1.
When the discharge of 4 is completed, the voltage switch element 13 becomes lower than the holding current and is turned off.
After this, if the dimming control switch 3 is turned on to the 200V side contact point again, the 200V power source 1 will turn on the light at 100%. Incidentally, if the operation of the dimming control switch 3 at the above-mentioned times _t1 to _t3 , etc. is performed by sequence control using a timer or the like, the brightness can be controlled very easily.

FIG. 5 shows another embodiment of the present invention, and is an example of a circuit when control at the dimming level as shown in FIG. 6 is required. However, in the embodiment circuit of FIG. 5, a saturable reactor 1 is connected in series to the fluorescent lamp 4 as a stabilizing element and a current limiting element for dimming.
6 is connected, and the control coil 18 of this saturable reactor 16 is connected to the resistor 11 and the voltage switch element 13.
The capacitor 14 is connected to both ends of the capacitor 14 via the diode 19, and the capacitor 14 is charged by the power input (correctly, the power input is full-wave rectified by the diode bridge 20). This lighting equipment is of a high frequency lighting type and is configured such that the output of the diode bridge 20 operates an inverter 21, and the output is applied to the fluorescent lamp 4 from the secondary winding of an output transformer 22. There is. FIG. 7 shows an explanatory diagram of the operation of the circuit shown in FIG. 5, in which a shows the receiving input voltage of lighting fixture B, b shows the dimming lighting level state, and c shows the state of the control current of the control coil 18 of the saturable reactor 16. are shown respectively.

Now, in the circuit shown in Figure 5, the dimmer control switch 3 is connected to the contact B, and the 200V power supply 1 is connected to the lighting fixture B.
is connected, the voltage switch element 13 is off in the same way as in the embodiment of FIG.
For this reason, the control coil 18 of the saturable reactor 16
Since no current flows through the lamp, the inductance of the saturable reactor 16 is large, and the fluorescent lamp 4 is lit at 50% dimming. After this, at time t ₁ , when the dimming control switch 3 is switched to the A contact side and the lighting fixture B is connected to the 230V power supply 2 side, the voltage switch element 13 is turned on and the control coil 18 is turned on as in the previous embodiment.
A control current i ₀ flows through, and this control current i ₀ causes 100%
All lights are turned on. Immediately after this, when the dimming control switch 3 is returned to the low contact side at time _t2 , the input voltage to the lighting fixture B becomes 200V, but the voltage switch element 13 remains on as in the previous embodiment. The control current i ₀ continues to flow through the control coil 18, and the control current i ₀ at this time due to the power supply voltage of 200V
Set to 65% dimming lighting state. Next, when the dimming control switch 3 is connected to the A contact point at time _t3 , the control current _i0 flowing through the control coil 18 increases by an amount corresponding to the increase in the power supply voltage, resulting in a 100% lighting state.

[Effect of idea]

Since the present invention is constructed as described above, there is no cause for noise generation due to output adjustment, so there is no need to take countermeasures against this, and the circuit configuration is also greatly simplified. Therefore, it has the advantage that output adjustment can be performed easily and inexpensively.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of power supply waveform distortion according to a conventional example, FIG. 2 is a circuit diagram of an embodiment of the present invention, and FIG. 3 is an explanatory diagram of a dimming level state to be realized by the circuit of FIG.
4 is an explanatory diagram of the operation of the circuit of FIG. 2, FIG. 5 is a circuit diagram of another embodiment of the present invention, FIG. 6 is an explanatory diagram of the dimming level state to be realized by the circuit of FIG. 7
The figure is an explanatory diagram of the operation of the circuit shown in FIG. 5, where 1 and 2 are power supplies, and B is a lighting fixture.

Claims (1)

[Claims for Utility Model Registration] (1) A plurality of power supplies with different voltages, a selection switch element that selects the power supply, a power-on switch element that controls power supply from the power supply, a selection switch element, and a power-on switch element. A load that is supplied with power from a power source via a power supply, and a power supply connected to both ends of the power supply through a power-on switch element, which generates an output when the power-on switch element is turned on, and outputs after a predetermined time delay after the power-on switch element is turned off. A power-on detection circuit section detects the power supply voltage and outputs an output when the detected voltage exceeds a predetermined value set between the plurality of power supply voltages, and outputs an output when the output of the power-on detection circuit section stops. A load output adjustment device comprising: a control circuit section that stops; and a load output adjustment circuit section that is interposed between a power source and a load and operates based on the output of the control circuit section to adjust the output of the load. (2) The plurality of power supplies mentioned above are composed of two types of power supplies, high and low, the selection switch element and the power-on switch element are composed of a three-contact changeover switch, and the power-on inspection detection circuit section is a rectifier circuit. It consists of a capacitor and a discharge resistor connected to the output terminal, and the control circuit section consists of a voltage responsive switch with a breakover voltage set between each of the above power supply voltages and a relay coil connected in series. It consists of a series circuit connected through a resistor, and the load output adjustment circuit section is composed of a parallel circuit consisting of an impedance and a relay contact that opens when the relay coil is energized, inserted in series between the power source and the load. A load output adjustment device according to claim 1 of the patented utility model.